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Simulation and measurement of dispersions in optical access networks
Kováč, Filip ; Münster, Petr (referee) ; Šifta, Radim (advisor)
Thesis deals with detailed description of the chromatic dispersion–CD and polarization mode dispersion–PMD. In theoretical part is dismantled at the beginning of words and mathematical principles of dispersion, further distribution of dispersion in terms of single-mode and multi-mode optic fibers through compensation, either fibers (chromatic dispersion) or systems (polarization mode dispersion). Theoretical part also consult the standard ITU-T specifically in term of fibers G.652, G.653, G.655, G.656, G.657, are described and compared. The penultimate section deals with major subject and by measuring both of the above dispersions. Finally, the theoretical part is devoted to optical access networks, which describes the optical access network such as its division and at the end describes the different types networks as APON/BPON, GPON, EPON, 10GEPON and XG-PON. The practical part is divided into measurement dispersions (EXFO FTB-5700) and simulation dispersions (OptSim). Both steps use the same type and length of fiber (6 km G.653, 20, 60 km G.652). According before creating the measured and simulation diagrams are obtained fibres parameters, which are finally compared.
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Dispersion effects in high-speed optical networks
Filip, Tomáš ; Šporik, Jan (referee) ; Tejkal, Vladimír (advisor)
This bachelor’s thesis is focusing on optical transmission principal, its transfer mediums and furthermore also with focusing on its advantages and disadvantages. First half of this thesis focuses on adverse influences, which affect signal transmission in optical networks, on dispersion influences, especially on Polarization Mode Dispersion (PMD). Second half of this thesis deals with measuring of properties of optical fibers, largely chromatic and polarization mode dispersion, used methods and its principals. Furthermore, there are mentioned current compensation possibilities. The seventh chapter deals with optical route simulation in OptiSystem and testing chosen compensation methods for bit rate 40Gb/s. In the last chapter there are elaborated results of real optical route measurements for Masaryk University.
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Measurement of the fiber optical transport links
Ambrož, Jan ; Škorpil, Vladislav (referee) ; Reichert, Pavel (advisor)
This thesis deals with the measurement of optical transport links. In particular, the measurement of attenuation, chromatic and polarization mode dispersion. Specic me- asurement systems using a WDM and passive optical networks. Within each chapter are listed the causes and eects restrictive factors and methods of measurement. In chapter Attenuation measurements are described radiation and material loss as the main causes of depression. Methods whitch are described two lengths, insert loss and reectometri. Chromatic dispersion at dierent speeds of various wavelengths limits systems with high transfer rate. Methods of measuring the phase shift, dierential phase shift, pulse time delay and interference. Polarization mode dispersion is a random phenomenon caused double refraction, must be measured after completion of the route. Scanning wavelen- gth, traditional and general interference, reectometri and the polarimetric are methods of measurement. It described the measurement of WDM systems in three stages of its build. In brief PON networks are presented, with the specicities of the measurement over splitter. Most chapters are supplemented by the results and conclusions of practical measurements. At the end of the work are given by the two standards deal with the measurement of optical transport links.
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Reproducibility and accuracy of polarization mode dispersion measurements
Kováč, Filip ; Brouček,, Jan (referee) ; Šifta, Radim (advisor)
Thesis is divided into two parts. The first part is written rather in theoretical way. It deals with general formation of the dispersion mathematically and verbally. It focuses on the chromatic and polarization mode dispersion. Different types of optical fibers for category G.65X are mentioned as well in connection with the ITU-T. Further attention is drawn first to compensation and then the measurement both of the mentioned dispersions. The thesis describes also analyzers and their main features. The second part is devoted to practical measurements of polarization mode dispersion. In the beginning there are described the components used for construction of the optical measurements and topologies. It is followed by an analysis of an each optical link. The results of these measurement methods and their mutual comparisons are at the end of this section. Measurements in temperature chamber is the subject of a further practical part, which from the beginning captures the essential features of the temperature chamber. This is followed by a description of the measurements, analyses and final valuation depending on the amount of polarization mode dispersion versus the temperature.
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Optical spectrometer designing
Dohnal, Marek ; Křivák, Petr (referee) ; Hudcová, Lucie (advisor)
This project focuses the problems of projection and design of optical instruments being instrumental to determination of elements in various material compounds. There are described here the structures of fundamental optical instruments and their possible variants, one of which has been chosen and further entered into details. The work specifically refers to an optical spectrometer, which by its nature, ranges the bands both of visible and near-infrared radiation. The work presents basic principles of particular parts, which the existent instrument can consist of, the advantages and disadvantages brought by the single parts. For specifically proposed configuration, intentionally set in such a way it uses state-of-the art measurement methods obtaining the best possible measurement results, the work analyzes in details the method of operation and solves numerically the theoretical assumptions for correct operation of the spectrometer. A constituent of the project is an experimental measurement testifying, with certain errors, to the theoretical solutions. The measurement errors that could result from chosen arrangement and chosen measurement method are numerically expressed in a separate sub-chapter. Further various calibration methods are mentioned, based on which the calibration method used during the experimental measurement was selected. The last part of project is focused on circumferential design of the optical spectrometer, where series of suitable circumferential elements was scrutinized. For basic elements there are presented their parameters and possible troubles related to the implementation. Furthermore the realisation of project was carried out and the spectrometer was assembled with the parts available in laboratory. The results were elaborated with a computer programme created specially for this application and then compared to a professional spectrometer.
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Measuring methods of key parameters in optical networks
Balon, Jiří ; Reichert, Pavel (referee) ; Tejkal, Vladimír (advisor)
The main goal of the master’s thesis was to familiarize with optical networks dilemma and its measuring during fabrication. The whole thesis is divided into several parts where the first part deals with optic fiber dilemma. It describes its kinds, properties and also suggests a basic principle of optic signal dispersion using these fibers. It describes also optical network FTTx architecture (Fiber To The x). The second part of the thesis focuses on methods of measuring key parameters of optical networks. Is brings out the methods of measuring optical loss and dispersive influences. The last and final part in focused on creating a methodical manual for measuring these networks during its fabrication and verifying measuring methods stated in the theoretical part inside a real network. Measuring was implemented on an optical network of Masaryk University in Brno.
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Techniques solving the fiber optic dispersion on current optical links
Prášil, Jiří ; Pfeifer, Václav (referee) ; Reichert, Pavel (advisor)
This diploma thesis deals with analysis of current diagnostic methods of optical networks, and it is focused on optical fiber dispersion in singlemode fibers. The work starts with a describtion chromatic dispersion and polarization mode dispersion, causes of and thein influence on the transmitted signal at the beginning. There are set out principles and their appropriate use in the list of measuring methods. Furthermore, the work are given the current possibilities for compensation above dispersions. The sixth chapter deals with the measurements and simulations of real routes in the OptiSystem. There are given appropriate compensation methods for the selected route speeds in the last chapter. The simulation is performed for the bit rate 2.5 Gbit / s, 10 Gbit / s and 40 Gbit / s.
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PMD - polarization mode dispersion and its effects on data transport
Trávníček, Pavel ; Dostál, Otto (referee) ; Filka, Miloslav (advisor)
My graduation thesis is concerned with the effect of polarization mode dispersion on transmitted signal by optical line. It describes external and internal causes of origination of polarization mode dispersion. On the basis of these effects there is a differential group delay (DGD). It is the time delay in meantime within individual modes. DGD results in a time extension of impulsion and limitation of maximum bit rate. This thesis contains localization methods of part of gossamer filament with increased value of PMD by POTDR method. This method is based on the principium of back dispersion and its modifications SOP a DOP. Very important chapter of this thesis is the measurement of the polarization mode dispersion. There are described methods of PMD measurement. It is the interferometric and polarimetric method and the method of state of polarization. The major part of this thesis is about the reduction of polarization mode dispersion effect. This part is divided into two parts. First part is about the methods of PMD effect reduction and the second one is about the PMD compensation. The discrepancy between these two parts is the reduction way of PMD effect on transmitted channel. The compensation use the compensation components inserted into the transmission path. By PMD reduction methods we can solve the problems from the view of changing of fibre or all cable. For better understanding of polarization mode dispersion effect there are simulated 4 optical lanes of various parameters. The simulation output is the eye diagram which provides the view at results of transmission lane. In the final part there is the evaluation of measured parameters of optical lanes simulated in a laboratory.
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Polarization mode dispersion
Turský, Aleš ; Dostál, Otto (referee) ; Filka, Miloslav (advisor)
The work deals with dispersive effects of single mode fibers. We learn about the chromatic dispersion, the main attention is paid to the Polarization Mode Dispersion. We clarify the root cause origin of the Polarization Mode Dispersion describing parameters and its effect on transmitted data. Further on, the works dedicates to measure methods of the Polarization Mode Dispersion which is the interferometric method or the POTDR method. We explain the ways of the PMD removal at contemporary optic routes and options of PMD compensation by using compensators of various types. There is also mentioned the possibility of profiting from the soliton transmission. The last chapter deals with measuring of a real optic route. It includes measured data and its evaluation due to the ITU-T demands.
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